Serum 25-hydroxyvitamin D Concentration Significantly Decreases in Patients with COVID-19 Pneumonia during the First 48 Hours after Hospital Admission.

It is unclear how ongoing inflammation in Coronavirus Disease 2019 (COVID-19) affects 25-hydroxyvitamin D (25[OH]D) concentration. The objective of our study was to examine serum 25(OH)D levels during COVID-19 pneumonia. Patients were admitted between 1 November and 31 December 2021. Blood samples were taken on admission (day 0) and every 24 h for the subsequent four days (day 1−4). On admission, 59% of patients were 25(OH)D sufficient (>30 ng/mL), and 41% had 25(OH)D inadequacy (<30 ng/mL). A significant fall in mean 25(OH)D concentration from admission to day 2 (first 48 h) was observed (30.7 ng/mL vs. 26.4 ng/mL; p < 0.0001). No subsequent significant change in 25(OH)D concentration was observed between day 2 and 3 (26.4 ng/mL vs. 25.9 ng/mL; p = 0.230) and day 3 and day 4 (25.8 ng/mL vs. 25.9 ng/mL; p = 0.703). The absolute 25(OH)D change between hospital admission and day 4 was 16% (4.8 ng/mL; p < 0.0001). On day 4, the number of patients with 25(OH)D inadequacy increased by 18% (p = 0.018). Therefore, serum 25(OH)D concentration after hospital admission in acutely ill COVID-19 patients should be interpreted with caution. Whether low 25(OH)D in COVID-19 reflects tissue level vitamin D deficiency or represents only a laboratory phenomenon remains to be elucidated in further prospective trials of vitamin D supplementation.

Patients with COVID-19 pneumonia with 25(OH)D levels lower than 12 ng/ml are at increased risk of death.

OBJECTIVES: There is no consensus on specific serum 25-hydroxy vitamin D (25(OH) D) levels associated with higher risk of severe outcome in patients with coronavirus disease 2019 (COVID-19). According to the literature patients with serum 25(OH) D levels <12 ng/ml are clearly deficient at all ages. Our aim was to assess COVID-19 mortality in the settings of severe 25(OH) D deficiency. A cohort study of 357 patients with COVID-19 was conducted. Subjects were monitored until discharge or in-hospital death. At admission, severity parameters (C-reactive protein (CRP), IL-6, Charlson comorbidity index, etc.) were assessed. These parameters were compared regarding 25(OH) D levels threshold 12 ng/ml, where values below 12 ng/ml were considered absolute vitamin D deficiency. RESULTS: 25(OH) D levels at the time of admission were independently associated with mortality (p <0.05). Nonsurvivors (N = 168) had lower 25(OH) D levels, SO2, higher age, CRP, viral load, and Charlson comorbidity index in comparison to survivors. Patients with serum 25(OH) D levels <12 ng/ml had higher mortality (55% vs 45 %), viral load (21.5 vs 23.1), and Charlson comorbidity index (5.3 vs 4.4) than those with serum 25(OH) D levels >12 ng/ml (p <0.05). CONCLUSIONS: Patients with COVID-19 with serum 25(OH) D levels <12 ng/ml have higher mortality. Among other factors, severe vitamin D deficiency likely leads to poor outcome.